Area Forecast Discussion
Issued by NWS Honolulu, HI

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591
FXHW60 PHFO 301403
AFDHFO

Area Forecast Discussion
National Weather Service Honolulu HI
403 AM HST Wed Sep 30 2026

.SYNOPSIS...
The center of Tropical Storm Nolo has moved out of Hawaii`s
offshore waters and will travel west over the Papahanaumokuakea
Marine National Monument waters the next several days. Bands of
showers along Nolo`s eastern flank will move up from the south and
pass across the islands the next few days with Oahu and Kauai
likely picking up the higher rainfall totals. Breezy southeast
winds will persist through the day, weaken through late week and
then transition back to trades early next week.


&&

.DISCUSSION...
At 3 AM HST, Nolo, which was downgraded to a tropical storm last
night, was located approximately 320 miles west of Barking Sands
Beach, Kauai, and is drifting west this morning. After slowly
wobbling westward the next couple of days, Nolo is currently
forecast by the National Hurricane Center to accelerate west this
weekend. Nolo`s far eastern outer bands are providing brief
periods of light to locally moderate rain as they quickly pass up
from the south over Kauai and Oahu. While the bulk of the heaviest
precipitation remains over the nearshore waters west of Niihau
and Kauai the next couple of days, Nolo`s westerly motion will
keep return periods of rain moving up from the south in the
forecast over mainly the western third of the state through early
Friday. Nuisance flooding of lower lying areas and street ponding
may occur, especially across Oahu and Kauai, the next couple of
days in the event that rainfall becomes more orientated to the
background southeast flow and exhibits more of a training nature.
Breezy southeast winds will continue across the state through
Thursday. Southeast-east winds will weaken over the weekend as
Nolo races away to the west and slackens the gradient back
toward the islands.

While Nolo will no longer directly impact the state, rain bands
along Nolo`s eastern periphery will move across within the
southeast flow pattern through Friday. An additional 4 to 6 inches
of rain with locally higher amounts near 10 inches, 3 to 5 inches
with locally higher amounts within upper terrain, is forecast for
Kauai and Oahu, respectively, the next few days. The quick
passage of these rain bands over a span of a few days keeps the
threat for any widespread significant flooding at bay. Big Island
will partially block Maui County from this east southeast flow
pattern. This will result in clearer skies over Maui County and
leeward Big Island as local land and sea breezes build interior
upslope afternoon cloud cover and produce brief showers. East
southeasterly winds will gradually weaken this weekend with trades
advecting in drier air expected to briefly return early next week.

An upper closed off low located northeast of the state is forecast
to sink south early next week. This will push a weak backdoor
front into the far eastern waters Monday or Tuesday. This weak
boundary stalling in the vicinity of Big Island will disrupt mid
to late week trade winds and ultimately produce very light and
variable breezes. Relatively drier air behind this northeast
boundary may keep dew points just low enough under this very
stagnant flow pattern in creating more bearable humidity levels.


&&

.AVIATION...
Moderate to breezy southeast winds will persist through this
afternoon then weaken heading into Thursday as Tropical Storm Nolo
gradually slides off to the west, away from the state. Outer rain
bands associated with Nolo will bring showers into mainly Kauai
and Oahu from the south over the next 24 hours, with Kauai
expecting the most coverage. MVFR and even IFR conditions will be
possible within these showers.

AIRMET Sierra for mountain obscuration is in effect for Kauai due
to the clouds and showers moving over the island from the south,
and across windward Oahu as showers persist over the Ko`olaus in
the southeast flow. This AIRMET will likely be needed through
most of today and may need to be expanded across more portions of
Oahu.

AIRMET Tango is in effect for low level turbulence west through
north of the island terrain over Kauai. This AIRMET may be needed
through most of today before the low level wind speeds decrease as
Nolo pushes further west.


&&

.MARINE...
Moderate to fresh south to southeast winds prevail for most areas
as Tropical Storm Nolo slowly drifts westward away from the
Hawaiian Islands. For waters surrounding Kauai, stronger southerly
winds will continue through the day. Gentle to fresh east to
southeast winds prevail across all waters by Thursday.

The moderate, medium period west to southwest swell originating
from Nolo will continue for Niihau and Kauai today. A small
background south swell continues for other islands. The next small
boost in south swell energy will arrive early next week Monday
and Tuesday.

Surf along other shores will remain small until moderate trades
return early next week providing a slight boost to east facing
shores. Multiple rounds of tiny northwest swell energy will reach
north and west facing shores into early next week as the storms
tracking near the Aleutian Islands becomes increasingly active.


&&

.FIRE WEATHER...
Fire weather conditions will improve through the remainder of the
week in response to higher southern moisture and moderate
southeasterlies.



&&

.HFO WATCHES/WARNINGS/ADVISORIES...
Small Craft Advisory until 6 PM HST this evening for Kauai
Channel-Kauai Leeward Waters-Kauai Northwest Waters-Kauai
Windward Waters.


&&

$$

DISCUSSION...Blood
AVIATION...Farris
MARINE...Bohlin